<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <title>下拉菜单</title>
    <style>
        .dropdown {
            position: relative;
            display: inline-block;
        }
        
        .dropdown-content {
            display: none;
            position: absolute;
            background-color: #f9f9f9;
            min-width: 160px;
            box-shadow: 0px 8px 16px 0px rgba(0, 0, 0, 0.2);
            padding: 12px 16px;
            background-color: red;
            
        }
        
        .dropdown:hover .dropdown-content {
            display: block;
    </style>
</head>

<body>   
    <div class="dropdown">
        <button>下拉菜单</button>
        <div class="dropdown-content">
            <p><a href="">菜鸟教程</a></p>
            <p><a href="">练习</a></p>
        </div>
</body>

</html>